H5N1亚型高致病性禽流感病毒NS基因的克隆及序列分析

Cloning and sequence analysis of NS gene of four H5N1 avian influenza virus strains

采用RT PCR技术对4株H5N1亚型高致病性禽流感病毒的NS基因进行了扩增,将获得的PCR产物分别与T载体连接,获得了4个毒株的NS基因阳性克隆。序列分析结果显示,分离毒株间的核苷酸同源率为90.2%～98.7%,氨基酸同源率为82.6%～97.8%。与其他毒株比较A Goose HLJ P46 2003(H5N1)和A Goose HLJ G2 2003(H5N1)株NS基因在第264～278位处发生了15个核苷酸缺失;A Goose Jilin W2 2004(H5N1)株NS1基因蛋白编码区的第652位碱基发生T C突变,成为终止密码子,造成NS1蛋白的C末端有13个氨基酸缺失。证实不同基因型的H5N1亚型禽流感病毒在我国家禽中同时存在;H9与H5亚型流感病毒基因间存在着广泛的遗传交换。

The NS genes were amplified and determined by RT-PCR technique from 4 strains of H5N1 subtype influenza A virus. The nucleotide sequence similarity among the 4 strains were between 90.2% to 98.7%, and the deduced amino acids similarity were between 82.6% to 97.8%. Fifteen nucleotides deletion between 264 nt and 278 nt was (observed) from the former two isolates(H5N1). The deletion of deduced thirteen amino acids on NS1N terminal end of A/Goose/Jilin/W2/2004(H5N1) was first observed to be in H5 subtype of virus, although it was reported in H9 subtypes of viruses early. The sequences homology between A/Goose/HLJ/G2/2003(H5N1) and A/Viet Nam/1196/04(H5N1) was 98.8%. The high (homology) indicates that the H5N1 isolates perhaps derived its NS gene from that of H9 viruses.